Segmental Motion of the Cervical Spine After Total Disc Replacement Using ActivC Versus Discectomy and Fusion Using Stand-alone Cage

Various designs of cervical total disc replacement (CTDR) have been introduced and employed in an attempt to avoid disadvantages of the fusion surgery. The purposes of this study were to evaluate the effects of the range of motion (ROM), the instantaneous center of rotation (ICR) and the facet joint force (FJF) with different constrained types of CTDR devices. A three-dimensional finite element (FE) model of intact cervical spine (C3-7) was made from CT scans of a normal person and validated. Postoperative FE models simulating CTDR implantation at the C5-6 disc space were made for CTDR-I (constrained design) and CTDR-II (nonconstrained design), respectively. Hybrid protocol (intact: 1 Nm) with a compressive follower load of 73.6 N was applied at the superior endplate of the C3 vertebral body. The inferior endplate of C7 vertebral body was constrained in all directions. At the index level, CTDR-I showed a higher increase in segmental motion and FJF than CTDR-II in extension, lateral bending and axial rotation. The CTDR-II with an elastomer-type core reproduced a near physiological ICR of the intact model in extension and axial rotation. Abnormal kinetic and kinematic changes related to the CTDR may induce surgical level problems and cause long-term failure of spinal surgery.

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Two-level lumbar total disc replacement: Functional outcomes and segmental motion after 4 years

Orthopaedics & Traumatology Surgery & Research ◽

10.1016/j.otsr.2014.10.014 ◽

2015 ◽

Vol 101 (1) ◽

pp. 17-21 ◽

Cited By ~ 7

Author(s):

S. Trincat ◽

G. Edgard-Rosa ◽

G. Geneste ◽

T. Marnay

Keyword(s):

Functional Outcomes ◽

Total Disc Replacement ◽

Disc Replacement ◽

Segmental Motion ◽

Lumbar Total Disc Replacement

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Early development and progression of heterotopic ossification in cervical total disc replacement

Journal of Neurosurgery Spine ◽

10.3171/2011.8.spine11303 ◽

2012 ◽

Vol 16 (1) ◽

pp. 31-36 ◽

Cited By ~ 38

Author(s):

Soo Eon Lee ◽

Chun Kee Chung ◽

Tae Ahn Jahng

Keyword(s):

Clinical Outcome ◽

Heterotopic Ossification ◽

Total Disc Replacement ◽

Disc Replacement ◽

Adjacent Segment ◽

Segmental Motion ◽

Cervical Total Disc Replacement ◽

The Mean ◽

Grade Iii

Object The purpose of cervical total disc replacement (TDR) is to decrease the incidence of adjacent segment disease through motion preservation. Heterotopic ossification (HO) is a well-known complication after hip and knee arthroplasties. There are few reports regarding HO in patients undergoing cervical TDR, however; and the occurrence of HO and its effects on cervical motion have rarely been reported. Moreover, temporal progression of HO has not been fully addressed. One goal of this study involved determining the incidence of HO following cervical TDR, as identified from plain radiographs, and demonstrating the progression of HO during the follow-up period. A second goal consisted of determining whether segmental motion could be preserved and identifying the relationship between HO and clinical outcomes. Methods The authors conducted a retrospective clinical and radiological study of 28 consecutive patients who underwent cervical TDR with Mobi-C prostheses (LDR Medical) between September 2006 and October 2008. Radiological outcomes were evaluated using lateral dynamic radiographs obtained preoperatively and at 1, 3, 6, 12, and 24 months postoperatively. The occurrence of HO was interpreted on lateral radiographs using the McAfee classification. Cervical range of motion (ROM) was also measured. The visual analog scale (VAS) and Neck Disability Index (NDI) were used to evaluate clinical outcome. Results The mean follow-up period was 21.6 ± 7.0 months, and the mean occurrence of HO was at 8.0 ± 6.6 months postoperatively. At the last follow-up, 18 (64.3%) of 28 patients had HO: Grade I, 6 patients; Grade II, 8 patients; Grade III, 3 patients; and Grade IV, 1 patient. Heterotopic ossification progression was proportional to the duration of follow-up; HO was present in 3 (10.7%) of 28 patients at 1 month; 7 (25.0%) of 28 patients at 3 months; 11 (42.3%) of 26 patients at 6 months; 15 (62.5%) of 24 patients at 12 months; and 17 (77.3%) of 22 patients at 24 months. Cervical ROM was preserved in Grades I and II HO but was restricted in Grades III and IV HO. Clinical improvement according to the VAS and NDI was not significantly correlated with the occurrence of HO. Conclusions The overall incidence of HO after cervical TDR was relatively high. Moreover, HO began unexpectedly to appear early after surgery. Heterotopic ossification progression was proportional to the time that had elapsed postoperatively. Grade III or IV HO can restrict the cervical ROM and may lead to spontaneous fusion; however, the occurrence of HO did not affect clinical outcome. The results of this study indicate that a high incidence of HO with the possibility of spontaneous fusion is to be expected during long-term follow-up and should be considered before performing cervical TDR.

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Lumbar Spine Capsule Strain After Total Disc Replacement

ASME 2010 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2010-19023 ◽

2010 ◽

Author(s):

Tomoyuki Takigawa ◽

Alejandro A. Espinoza Orías ◽

Howard S. An ◽

Peter Simon ◽

Keizo Sugisaki ◽

...

Keyword(s):

Low Back Pain ◽

Back Pain ◽

Facet Joint ◽

Total Disc Replacement ◽

Clinical Results ◽

Disc Replacement ◽

Segmental Motion ◽

Low Back ◽

Disc Disease ◽

Poor Outcomes

Degenerative disc disease is a common cause for low back pain, and sometimes requires surgical treatment. Total disc replacement (TDR) is one such surgical option performed to remove the painful disc and preserve segmental motion. However, TDR clinical results are not always satisfactory. Altered kinematics and residual low back pain have been reported as frequent poor outcomes. The facet joint is a pure articular joint and can be a pain generator. Although the effect of TDR on ROMs (ranges of motion) and facet contact force is relatively well studied, the influence of TDR on facet capsules has not been clarified yet. The purpose of this study was to evaluate the effect of TDR on facet joint capsule strain.

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Heterotopic ossification after cervical total disc replacement: determination by CT and effects on clinical outcomes

Journal of Neurosurgery Spine ◽

10.3171/2010.11.spine10444 ◽

2011 ◽

Vol 14 (4) ◽

pp. 457-465 ◽

Cited By ~ 61

Author(s):

Tsung-Hsi Tu ◽

Jau-Ching Wu ◽

Wen-Cheng Huang ◽

Wan-Yuo Guo ◽

Ching-Lan Wu ◽

...

Keyword(s):

Ct Scan ◽

Heterotopic Ossification ◽

Total Disc Replacement ◽

Disc Replacement ◽

Segmental Motion ◽

Cervical Total Disc Replacement ◽

Plain Radiographs ◽

Bryan Disc ◽

The Mean

Object Heterotopic ossification (HO) after cervical total disc replacement (TDR) has been reported to impede artificial disc motion. In all previously reported cases of HO, assessment was based on plain radiographs. The authors hypothesized that CT scan is a more sensitive and accurate detector. The aims of this study were to assess the actual incidence of HO and its effect on outcome in a cohort of patients undergoing cervical TDR with the Bryan disc and to compare HO detection by means of plain radiographs and CT. Methods The authors retrospectively assessed data from medical records, radiological studies, and clinical evaluations of patients who underwent 1- or 2-level cervical TDR with the Bryan disc and were followed up for more than 12 months. The presence and grading of HO according to the McAfee classification were assessed by CT scan, and these findings were compared with findings on plain radiographs. Thirty-six patients (mean age 46.61 ± 7.24 years; range 29–60 years; 21 men and 15 women) who underwent Bryan TDR at 52 levels were included in the study. The mean duration of CT follow-up was 19.03 ± 4.64 months; the mean duration of clinical follow-up was 26.78 ± 7.20 months. Results On the basis of CT, HO was identified in 18 (50%) of 36 patients and 25 (48.1%) of 52 levels treated. Grade 1 HO was present in 9 of the levels treated (17.3%), Grade 2 in 13 levels (25.0%), Grade 3 in 2 levels (3.8%), and Grade 4 in 1 level (1.9%). Nineteen (76%) of the 25 affected levels were in patients who had undergone 2-level TDR. There was no significant association with patient sex or disc pathology. There was a tendency for HO development among older patients, but this finding was not statistically significant (mean age 48.8 ± 6.8 in patients with HO vs 44.4 ± 7.2 in those without HO, p = 0.065). Although HO was found in 25 levels, 96.2% of the treated levels (50 of 52) had segmental range of motion on dynamic (flexion and extension) radiographs. The concordance between HO grading by CT and radiography was high, with an intraclass correlation coefficient of 0.822 (lower limit of 95% CI: 0.710, p < 0.001). Patients who had HO had the same clinical success rate as those who did not (94.4% vs 94.4%, p = 1.00). The visual analog scale scores for neck and arm pain were significantly improved in both the HO and the non-HO group. Conclusions The rate of HO detected by CT scan in this cohort of patients undergoing cervical TDR with a Bryan disc was 48.1% per level treated and 50% per patient with minimal limitation of segmental motion (96.2% of levels remained mobile), but plain radiograph is an acceptable detection tool. Two-level surgery has a higher risk of HO, although development of HO does not affect clinical outcome.

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Artificial total disc replacement versus fusion for the cervical spine: a systematic review. Zechmeister I, Winkler R, Mad P. Eur Spine J 2010 Oct 10. [Epub ahead of print]

The Spine Journal ◽

10.1016/j.spinee.2010.11.024 ◽

2011 ◽

Vol 11 (2) ◽

pp. 159

Keyword(s):

Systematic Review ◽

Cervical Spine ◽

Total Disc Replacement ◽

Disc Replacement

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In which cases do surgeons specializing in total disc replacement perform fusion in patients with cervical spine symptoms?

European Spine Journal ◽

10.1007/s00586-019-06275-9 ◽

2020 ◽

Vol 29 (11) ◽

pp. 2665-2669

Author(s):

Richard D. Guyer ◽

Donna D. Ohnmeiss ◽

Scott L. Blumenthal ◽

Jack E. Zigler

Keyword(s):

Cervical Spine ◽

Total Disc Replacement ◽

Disc Replacement

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Investigation into Cervical Spine Biomechanics Following Single, Multilevel and Hybrid Disc Replacement Surgery with Dynamic Cervical Implant and Fusion: A Finite Element Study

Bioengineering ◽

10.3390/bioengineering9010016 ◽

2022 ◽

Vol 9 (1) ◽

pp. 16

Author(s):

Muzammil Mumtaz ◽

Iman Zafarparandeh ◽

Deniz Ufuk Erbulut

Keyword(s):

Cervical Spine ◽

Standard Procedure ◽

Total Disc Replacement ◽

Disc Replacement ◽

Von Mises Stress ◽

Adjacent Segment ◽

Fusion Model ◽

Hybrid Surgery ◽

Maximum Increase ◽

Flexion Extension

Cervical fusion has been a standard procedure for treating abnormalities associated with the cervical spine. However, the reliability of anterior cervical discectomy and fusion (ACDF) has become arguable due to its adverse effects on the biomechanics of adjacent segments. One of the drawbacks associated with ACDF is adjacent segment degeneration (ASD), which has served as the base for the development of dynamic stabilization systems (DSS) and total disc replacement (TDR) devices for cervical spine. However, the hybrid surgical technique has also gained popularity recently, but its effect on the biomechanics of cervical spine is not well researched. Thus, the objective of this FE study was to draw a comparison among single-level, bi-level, and hybrid surgery with dynamic cervical implants (DCIs) with traditional fusion. Reductions in the range of motion (ROM) for all the implanted models were observed for all the motions except extension, compared to for the intact model. The maximum increase in the ROM of 42% was observed at segments C5–C6 in the hybrid DCI model. The maximum increase in the adjacent segment’s ROM of 8.7% was observed in the multilevel fusion model. The maximum von Mises stress in the implant was highest for the multilevel DCI model. Our study also showed that the shape of the DCI permitted flexion/extension relatively more compared to lateral bending and axial rotation.

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